1. Field of the Invention
The present invention relates in general to a method for producing aloe products and in particular to a process for utilizing the waste residue from the hand-filleted process of aloe leaves to produce an aloe liquid that has calcium, magnesium, malic acid, and total solids in quantities that generally far exceed the parameters of quality established by the International Aloe Science Council.
2. Description of Related Art
The growing, preparation, and medicinal uses of the yellow sap of the aloe plant were known to the natives of the cape region of Africa long before it was made known to the European colonists and long before the early 1770's.
The aloe leaf consists of three layers. The first is the thick outer green rind. The second is a viscous, jelly-like mucilage layer into which vascular bundles, attached to the inner surface of the rind, protrude. The third is the fillet proper which has a structural integrity consisting of hexagonal structures containing the fillet fluid.
During the growth of the aloe plant, the materials of the mucilage layer, subsequent to their synthesis, are distributed to the storage cells (cellulose-reinforced hexagons) of the fillet, a process which is accompanied by dilution owing to the water which is stored in the fillet cells. The fillet consists of more than 99% water.
The pericyclic cells located at the top of the vascular bundles contain a yellow liquid called "yellow sap" or "latex". This material contains high concentrations of aloin and similar anthraquinones that exert a powerful laxative action when taken internally. Indeed, during the 18th to early 20th century, this yellow sap was collected and processed into a hard blackish material, the major product of the "laxative" trade era, while the rest of the leaf and its other constituents were discarded.
In order to avoid contaminating the internal fillet with the yellow sap, the traditional hand-filleting method of processing aloe leaves was developed. In this method, the lower one inch of the leaf base, the tapering point (2-4 inches) of the leaf top, and the short, sharp spines located along the leaf margins are removed by a sharp knife. The knife is then introduced into the mucilage layer below the green rind to avoid the vascular bundles and the top rind is removed. The bottom rind is similarly removed and the rind parts, to which a significant amount of mucilage remains attached, are discarded. Another portion of the mucilage layer is accumulated on top of the filleting table and is also discarded. As an additional procedure to limit inclusion of the inadvertent laxative anthraquinones, the fillets may be washed in water removing a majority of the deep layer of mucilage attached to the outer surface of the structurally integral fillet.
A second method of processing aloe leaves was developed using the whole leaf and is called the "whole leaf aloe process". In this process, the base, tip, and lateral spines of the aloe leaf are removed as previously stated leaving intact the thick outer green rinds. The leaf is then cut into sections and ground into a particulate slurry material. The slurry is then treated with special chemical products that break down the hexagonal structure of the fillet releasing the constituents. By means of a series of coarse screening filters or passage through a juice press, the rind particles are removed. The remaining juice is then passed through various filtering columns which remove the undesirable laxative agents. This process, performed properly, can produce a constituent-rich juice virtually free of the laxative anthraquinones. This process, developed in the 1980's is considerably less labor intensive and is more cost effective.
In this process, the large amount of water in the fillet in the leaf (50%+) is therefore processed and dilutes the valuable constituents in the aloe product.
In order to increase the desirable constituents of processed aloe in the final product, the elements in the product may be concentrated by (1) heat, (2) heat and vacuum, and (3) reverse osmosis.
Variously processed aloe juices can be reduced to powder form which improves shelf life compared to liquid products and eliminates the cost of shipping water.
In the spray-dried powder process, the liquid aloe is sprayed onto a matrix, usually high molecular weight maltodextrins, that usually constitute about 50% or more of the final product, using high heat. The high heat exposure changes to some degree some of the potentially beneficial constituents.
The lyophilized or freeze-dried powder utilizes cold (about -85.degree. C.) and vacuum (usually about one-third atmosphere) which causes evaporation and sublimation of only the water. Heat-induced changes in the beneficial constituents are avoided but the process is considerably more expensive than the spray-dried process.
In the third process, fillets of aloe can be reduced to dehydrated pellets by placing them in a commercial-scale vegetable dehydrator operated at relatively low temperatures (slightly above body temperature) but for many hours. The dehydrated pellets are then ground to a fine powder.
The constituents that are most constant in the aloe plant and that are used as a standard by which to judge an aloe product are (1) total solids, (2) calcium, (3) magnesium, and (4) malic acid. The standard for calcium in the hand-filleted product is 241 milligrams per liter. The standard for magnesium in the hand-filleted product is 58.4 milligrams per liter. The standard for malic acid in the hand-filleted product is 2028 milligrams per liter. Finally, the standard for solids in the hand-filleted aloe product is 0.83 percent.
It has been known that the discarded residue from the filleting process that includes the rind contains a significant amount of mucilage that remains attached. It has been discovered that the highest concentration of potentially beneficial aloe constituents are found in this mucilage along with the rind as this layer represents the leaf constituents synthesized by the vascular bundle cells and powered by the energy developed in the green chlorophyll-containing rind cells through sun-induced photosynthesis.
It would be advantageous to make use of the discarded residue of the filleted process to have an aloe product that contains an enviably high concentration of desirable constituents that are virtually free of undesirable laxative anthraquinones. This novel process produces a product containing desirable constituents that may exceed those of aloe products subjected to concentration procedures intended to increase these desirable constituents.